As in all fields of graphic reproduction, the resolution or sharpness of the edge of an image is important. The optical image to which a charged photoconductor is exposed can be made quite sharp by the use of a lens system of high resolving power. The degree to which a photoconductor can retain the latent electrostatic image formed by the exposing step depends upon the composition and nature of the particular photoconductor. For purposes of illustration, I will assume blurred electrostatic images occur either because the original is blurred or as an incident of the exposing step of the reproduction process. The measurement of the resolution of the system, that is, the optics and the photoconductor, can be measured in terms of percentage modulation transfer function. My method and apparatus increase the percentage modulation for all frequencies below the upper frequency limit of the system. This is especially apparent when a blurred original is being reproduced.